Permanent surgically induced lesions in the subcaudate area which encompasses a large assembly of axonal projections have been used to treat a number of neurological and psychiatric disorders. Although these procedures have sometimes been effective, they were often associated with serious complications including decreased motivation and loss of interest as well as some neuropsychological disorders and cognitive disturbances.
Deep brain stimulation or the infusion of drugs into the brain has been conducted to modulate the neural activity in disease affected circuitry and improve neurological and psychiatric function while avoiding the cost of irreversible side effects. The use of deep brain stimulation is taught for example in U.S. Pat. No. 5,188,104, U.S. Pat. No. 5,263,480, U.S. Pat. No. 5,782,798, U.S. Pat. No. 6,128,537 and U.S. Pat. No. 6,871,098 and U.S. Pat. No. 6,950,707 (the disclosures of which are incorporated herein by reference in their entirety) for treating certain brain areas and disorders.
While the prior art has used deep brain stimulation, it is desirable to use such stimulation for the treatment of neurological and psychiatric disorders manifested by abnormal neural activity in regions receiving inputs or relaying outputs through the subcaudate area of the brain. This has not been previously demonstrated and therefore there remains a need to try and treat such disorders where tracks in the subcaudate region are abnormally affected.